The invention relates to a device for selectively positioning at least one cylinder in a printing machine, the cylinder being rotatably mounted in a carrier and, together with the carrier, forming a unit that is adjustable into different positions.
Positioning devices of this type are used to adjust the cylinder into an operating position and into a rest or maintenance position within the printing machine.
For example, a coating device for a printing machine is described in U.S. Pat. No. 4,617,865. The device includes a frame which, guided by rails, is adjustable linearly along a first direction of motion. In the frame, an auxiliary frame is mounted so that it is pivotable in a second direction of motion. The auxiliary frame carries a trough or pan, a feed roller and a coating roller. The coating roller can be brought into contact with a rubber blanket cylinder by pivoting the auxiliary frame. The auxiliary frame is unable to be placed onto the rail but instead is guided permanently over the frame by the rail.
Furthermore, the published German Patent Document DE 69022419 T2, corresponding to U.S. Pat. No. 4,934,305, describes a further coating device constructed as a unit including a housing and a coating cylinder mounted in the latter. The housing is mounted so that it can slide on rails but cannot be placed onto the rails. The unit can be adjusted only along a single direction of motion.
The aforedescribed positioning devices are well suited for the application present in each case, respectively, but cannot be used for other applications.
It is accordingly an object of the invention, therefore, to provide a further positioning device that is useful for many applications in printing machines.
With the foregoing and other objects in view, there is provided, in accordance with one aspect of the invention, a device for selectively positioning at least one cylinder in a printing machine, the cylinder being rotatably mounted in a carrier and, together with the carrier, forming a unit that is adjustable into different positions, comprising a guide, and a drive for adjusting one of the unit and the carrier, respectively, along a first direction of motion and placing it on the guide for guidingly adjusting it along a second direction of motion.
In accordance with another feature of the invention, the unit guided by the guide is adjustable from a rest position into an operating position, and the cylinder, when in the operating position, cooperatively engages a cylinder guiding printing material.
In accordance with a further feature of the invention, the drive is a pull mechanism drive.
In accordance with an added feature of the invention, the guide includes at least one eccentric that is rotatable about an eccentric bearing.
In accordance with an additional feature of the invention, the eccentric is mounted in a pivoting lever that is pivotable about one of a pivot bearing and a further eccentric, respectively.
In accordance with yet another feature of the invention, the guide includes at least one roller.
In accordance with yet a further feature of the invention, the carrier is formed with a guide surface, and is disposable on the roller with the guide surface thereof inclined to the horizontal.
In accordance with yet an added feature of the invention, the positioning device includes at least another cylinder rotatably mounted in the carrier.
In accordance with yet an additional feature of the invention, the one cylinder and the other cylinder mounted in the carrier are in circumferential contact with one another.
In accordance with still another feature of the invention, the one cylinder is an applicator cylinder for applying a coating to a printing material.
In accordance with still a further feature of the invention, the unit is formed as a module that is selectively replaceable by another module of different construction.
In accordance with another aspect of the invention, there is provided a printing machine including at least one positioning device having at least one of the foregoing features.
In the positioning device according to the invention, the guide can function as a stop limiting the adjustment travel and whereon the carrier is disposable. The cylinder mounted in the carrier should also be understood to mean a roller or roll. The cylinder mounted in the carrier is adjustable along the first adjustment direction from a first position into a second position, and along the second adjustment direction, that is different from the first adjustment direction, from the second position into a third position. The first position may be a maintenance position, for example for cleaning or replacing the unit, the second position may be a rest position, for example, with a slight spacing of the outer or jacket surface thereof between the cylinder mounted in the carrier and a further cylinder mounted in the machine frame, and the third position may be an operating position, for example, with an even smaller spacing or with contact between the cylinder mounted in the carrier and the further cylinder. The guide may be, for example, a rail guide, whereon the unit, constructed as a slide or carriage, slides or rolls. The unit may be linearly adjustable in one or both directions of motion. The unit may also be adjustable nonlinearly in one or both directions of motion, for example, by being pivoted on a path having the shape of a circular arc. The unit can preferably be adjusted approximately linearly in both directions of motion.
An advantageous embodiment developing an improvement in the invention is calls for the unit, guided by the guide, to be adjustable from a rest position into an operating position, the cylinder, when in the operating position, cooperating with a cylinder guiding printing material.
The cylinder guiding printing material may be an impression cylinder respectively guiding and transporting a printing-material web and a printing-material sheet, respectively, or a sheet transfer drum, it being possible for the printing material supported by the impression cylinder or by the sheet transfer drum to be printed, varnished or processed by the cylinder mounted in the carrier.
In a further embodiment, the drive of the invention is a pull mechanism drive.
Pull mechanism drives include, for example, winches, V-belt drives acting by friction lock, and formlockingly acting toothed-belt drives. In this regard, it is noted that a formlocking connection is one that connects two elements together due to the shape of the elements themselves, as opposed to a forcelocking connection that locks the elements together by force external to the elements. The pull mechanism drive is preferably constructed as a chain drive or transmission, by which a high positional accuracy of the unit is achieved. In this case, the pull mechanism drive may be a link chain.
In a further embodiment, the guide has at least one eccentric that is rotatable about the eccentric bearing of the guide.
The eccentric can also be constructed as an eccentric roller that is rotatable about the off-center eccentric bearing.
In a further embodiment, the eccentric is mounted in a pivoting lever that is pivotable about a pivot bearing or in a further eccentric.
The unit supported by the eccentric can be adjusted both by an adjustment of the pivoting lever and by an adjustment of the eccentric, it being possible for the pivoting lever and the eccentric to be adjusted independently of one another. By pivoting the pivoting lever, the cylinder mounted in the carrier can be brought into contact with the impression cylinder mounted in the machine frame and brought out of contact with the cylinder again. In this way, it is possible, for example, for the pressure to be switched on and off. By rotating the eccentric relative to the pivoting lever, the relative position of the unit to the pivoting lever can be adjusted. In this way, for example, an adaptation to the thickness of a printing material can be implemented and, for this purpose, a spacing between the circumferential outer surfaces of the cylinder, that is mounted in the carrier and located in the operating position, and of the impression cylinder can be adjustable. Instead of the pivoting lever, a further rotatable eccentric can also be used, wherein the first-mentioned eccentric is rotatably mounted.
In a further embodiment, the guide has at least one roller.
The roller can be the eccentric roller arranged on the pivoting lever or another roller rotatably mounted, for example, in the machine frame. The guide can also include a number of rollers, preferably both the eccentric roller and the stationary roller mounted in the machine frame being present.
In a further embodiment, the carrier is disposable on the roller with a guide surface of the carrier being inclined with respect to the horizontal.
A carrier with the inclined guide surface resting on the stationary roller is guided particularly favorably. It is preferable if the inclination of the guide surface rises towards the impression cylinder and away from the unit.
In another embodiment, at least a further cylinder is rotatably mounted in the carrier.
The one cylinder and the further cylinder mounted in the carrier are preferably arranged axially parallel to one another.
In a further embodiment, the one cylinder and the further cylinder mounted in the carrier are in circumferential contact with one another.
The cylinders can also be arranged with a very slight spacing between the circumferential outer or jacket surfaces thereof and, for example, can be adjusted to a selective gap dimension.
In a further embodiment, the cylinder is an applicator cylinder for applying a coating to a printing material.
The coating may be a powdered toner or preferably a coating liquid. In the last-mentioned case, the further cylinder mounted in the carrier may be a metering or half-tone roller that is assigned to the coating cylinder and feeds the coating liquid to the applicator cylinder.
In a further embodiment, the unit is a module that is selectively replaceable as desired by a further module of different construction.
For example, different varnishing modules, impression or numbering modules, printing modules, processing modules and other finishing modules can be inserted into the device. The varnishing modules may be of different constructions with respect to the feeding of varnish to the cylinder mounted in the carrier, and can be installed depending upon the viscosity and type of varnish that is used. For example, in the case of a varnishing or coating module, provision may be made for a supply of varnish or coating liquid with a chamber-type doctor blade assigned to the half-tone roller and, in the case of a module of a different type, with a dip roller that is assigned to the metering roller, and in the case of a further module of this type, with a roller wedge. In the case of the last-mentioned system, the liquid is fillable or pourable into the roller wedge that is open at the top and formed by two rollers which are in contact with one another, the wedge forming a liquid reservoir. The printing modules and the imprinting or numbering modules may be different with regard to the printing process, and may be constructed to correspond, for example, to a letterpress, planographic, gravure, flexographic or non-impact printing principle. The processing modules may be constructed, for example, as cutting, stamping, grooving, embossing, smoothing or perforating modules. All the aforementioned modules can be used selectively and interchangeably among one another.
The device according to the invention can be used in rotary printing machines which print web-like or sheet-like printing material and which may be constructed as an offset printing machine.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a positioning device in a printing machine, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, wherein: